How to turn gpclibPermit() to TRUE

Question

When I run gpclibPermit(), I've got the answer FALSE. How can I change it to be TRUE?

Answer 1

I've struggled with the gpclibPermit issue myself. You don't provide a reproducible example, but I am guessing that you are having a sesion like this:

library(maptools) Checking rgeos availability: FALSE Note: when rgeos is not available, polygon geometry computations in maptools depend      on gpclib, which has a restricted licence. It is disabled by default; to enable gpclib, type gpclibPermit() > gpclibPermitStatus() [1] FALSE > gpclibPermit() [1] FALSE > gpclibPermitStatus() [1] FALSE 

At this point it helps to look at what gpclibPermit and gpclibPermitStatus actually do:

> gpclibPermit function ()   { if ("gpclib" %in% .packages(all.available = TRUE))      assign("gpclib", TRUE, envir = .MAPTOOLS_CACHE) if (gpclibPermitStatus())      warning("support for gpclib will be withdrawn from maptools at the next major release") gpclibPermitStatus() } <environment: namespace:maptools> > gpclibPermitStatus function ()      get("gpclib", envir = .MAPTOOLS_CACHE) <environment: namespace:maptools> 

That is, you can't give maptools the permission to use gpclib unless you have the package gpclib installed.

install.packages("gpclib") library(maptools) Loading required package: sp Checking rgeos availability: FALSE Note: when rgeos is not available, polygon geometry computations in maptools depend on gpclib,  which has a restricted licence. It is disabled by default; to enable gpclib, type gpclibPermit()  > gpclibPermit() [1] TRUE Warning message: In gpclibPermit() : support for gpclib will be withdrawn from maptools at the next major release > gpclibPermitStatus() [1] TRUE 

Answer 2

I had this issue myself and found it easiest to install rgeos, and ensure that it was attached prior to attaching maptools

library(ggplot2) library(rgeos) library(maptools)